Production of artificial fibers of polymeric materials



Patented Feb. 17 1953 PRODUCTION OF ARTIFICIAL FIBERS OF POLYMERICMATERIALS Clement Henry Bamford and William Edward Hanby, Maidenhead,and Frank Happey, Bingley, England, assignors to Courtaulds Limited,London, England, a British company No Drawing. Application April 12,1951, Serial No. 220,732. In Great Britain May 12, 1950 7 Claims.

This invention relates to the production of artificial fibres ofpolymeric compounds and particularly to the production of fibres ofsynthetic polypeptides by polymerising anhydrocarboxyamino-acids havingthe general formula:

,a lower aliphatic carboxylic acid, a halogen-subsstituted loweraliphatic acid or mixtures of these compounds. 'lcified are meta-cresol,formic acid, dichloracetic Examples of suitable solvents speacid andtrichloracetic acid. It'is stated ,in the specification of applicationSerial No. 159,391 filed May 1, 1950, or its continuation-in-part Serial:No. 221,144, filed April 18, 1951, that fibres ob tained using formicacid as solvent generally have a ,8 configuration whereas fibresobtained using phenols, dichloracetic acid and trichloracetic acid assolvents have generally an a configuration, A number of polypeptidefibres having an a configuration tend to swell or even dissolve inbenzene, carbon tetrachloride and similar nonpolar organic liquids someof which find use as dry-cleaning agents.

The object of the present invention is toreduoe V the tendency for thesepolypeptide fibres to dissolve or swell in non-polar organic liquids.

According to the present invention, a process for the production ofsynthetic polypeptide fibres comprises extruding through a jet intoaisetting medium a solution of the polypeptide in a solvent giving an aconfiguration, for example, metacresol, dichloracetic acid ortrichloracetic acid and then treating the resultant thread with a bathcomprising at least one aliphatic monocarboxylic acid containing fromone tosix- .'c'arbon atoms per molecule or a like acid containing on thea carbon atom a bromine, phenyl or mercaptan group, so that at leastpart of the fibresis converted into the [3 configuration. Examples of'suitablemonocarboxylic acids are formic acid,

, 2 glacial acetic acid, propionic acid, n-butyric acid, iso-butyricacid, n-caproic acid, iso-caproic acid and crotonic acid. Examples of-a-SllbStll7llt6d acids which may be used are bromoacetic acid,phenylacetic acid, a-bromo propionic acid, a. bromo butyric acid, abromo-n-valeric acid and thioglycollic acid. Formic acid is thepreferred acid. The extruded fibres While in the a form may be stretchedbefore being treated with the acid in accordance with the invention.

The polypeptide solutions may be wet spun, or they may be dry spun, forexample into hot air. Suitable coagulant liquids for use in theinvention are water, ethyl alcohol, methyl alcohol and aqueous alcoholsas described in the specification of application Serial No. 159,391.

The treatment according to the invention may be eiiected by immersingthe fibres for a short time, for example, from 1 to 3 minutes in aliquid acid at ordinary temperatures although in some cases a shortertime is effective; if the particular acid is solid at ordinarytemperatures, such acid may be used in the form of an aqueous oralcoholic solution. When formic acid is used the acid bath may consistof 100 per cent formic acid or aqueous or alcoholic solutions of formicacid containing at least 75 per cent by volume of formic acid.

' The present invention is illustrated by the following examples inwhich percentages are by weight unless otherwise stated.

Example 1 A copolymer of DL-p-phenylalanine and DL- leucine was preparedas described in the specification of application Serial No. 159,392 asfollows: 60 millimols of anhydrocarboxy-DL-leucine and 60 millimols ofanhydrocarboxy-DL-fi-phenylalanine were dissolved in approximately threetimes their total weight of nitro-benzene. 0.15 millimol of sarcosinedimethylamide in benzene solution was added as initiator and the mixturewas allowed to stand for 3 days at centrigrade. At the end of this timepolymerisation was substantially completed and evolution of carbondioxide had substantially ceased. The polymer was precipitated by addingpetroleum ether, the

precipitate was filtered ofi, washed with petroleum ether and dried.

The cep'olyrn'er obtained, which was soluble in benzene and in carbontetrachloride, was dissolved in trichloracetic acid containing 10 percent of water to form ,al5 per cent solution and "the solution wasextruded'into abath of water "at ordinary temperature (20 centigrade).'The fibres so produced, which had an a configuration, were withdrawnfrom the bath of water, passed through a bath of formic acid at 20centigrade, and dried at 100 centigrade.

The fibres obtained had a B. configuration and were no longer soluble inbenzene or carbon tetrachloride.

Example 2 A polymeric DL-p-phenylalanine,produced as described inExample 2 of the specification of ape plication Serial No. 159,391 wasdissolved in metacresol to form a 15 per cent solution and the solu-'tion was extruded into a bath of ethyl alcohol at 20 centigrade. Thefibres so produced, which had an a configuration, were withdrawn fromthe alcohol bath, passed through a bath of formic acid at 20 centigradecontaining about 2 per cent by volume of water, and dried at 100centigrade.

The fibres obtained had a 13 configuration.

Example 3 Example 4 Th cep ym r o -fi-p enylalanin an D .le e ne asused. i Example 1 w s dry sp n n hot air fr m a 30 p r nt sol on in methn chloride. The resulting fibre was oriented by str n 200 p cent inSteam, passed t rou h a bath of formic acid containing per cent byvolume of water, the bath being at 20 centigrade, and dried at 100centigradei The fibres obtaine ha a is confi ura ion- Example 5 Fibresof the copolymer of DLepephenylalanine+DL-.1eucine prepared as describedExample 1 were immersed for one minute in glacial acetic acid at 20centigrade and then dried at 100 centigrade. The fibres obtained wereinsoluble in benzene whereas the fibres before treatment were readilysoluble in benzene.

Examples 6 to 11 Fibres of the benzene soluble copolyiner described inExample 1 were immersed for 3 minutes in one of each of the followingbaths at 20 centimixture oi equal volumes of ethanol and water.

The fibres were then washed with ether and ried. T pr duc s obta ned ineach examp e were insoluble in benzene.

. Examples 12 to 14 I F bres e he be zene-soluble eopolymer escr bed inExample l were immersed ter 1 minu e 4 in one of each of the followingbaths at 20 centigrade:

Example 12 n-butyric acid. Example 13 isobutyric acid, Example 14n-caproic acid.

The fibres were then washed with ether and -dried. The products obtainedin each example were insoluble benzene.

' Examples 15 to 17 A copolymer prepared from equimolecular proportionsof 'DL-B-phenylalanine, DL-leucine and -benzyl-DL-glutamate was preparedby the method described in application Serial No. 159,392 using 1/800roportion of carcosine dimethylamideas initiator. The product was spun Iinto fibres from benzene solution using petroleum ether as coagulantbath.

Samples of the fibres were then treated as follows:

Example l5 Immersed for 1 minute in formic acid and then dried directlyat 100 centigrade.

Example 16 Immersed for 3 minutes in glacial acetic acid,

washed with ether and dried.

Example 17 Immersed for 1 minute in propionic acid and dried directly at100 centigrade.

. of ti e not xe e n a t 3 i ut s in a at comprising at lea'st'onIacidchosen from the group consisting of. aliphatic. monocarboxyiic acidscontaining from one to, six carbon atoms per molecule and such acidscontaining on the a carbon atom a radical chosen from the groupconsisting of bromide, phenyl and mercaptan groups, so that at leastpart of the fibres is converted into the a configuration. i

v 2. A process forthe production of fibres from fibre-formingpolypeptides obtained by polynierising alphaanhydrocarboxyamino-carboxylic acids comprising extruding through a jetinto I a setting medium a solution of the polypeptide indichloroaceticacid andthen treating the resultant thread for a period of time notexceeding about 3 minutes in a bath comprising at least one acid chosenfrom the group consisting of aliphatic monocarboxylic acids containingfrom one to six carbon atoms per molecule and such acids containing onthe carbon atom a radical cho en f om th r up Consisting o br id phenyland mercaptan groups, so that at least part of the fibres is convertedinto the B-configuration.

3, A process for the production of fibres from fibre-formingpolypeptides obtained by polymerising alphaanhydrocarboxyamino-carboxylic acids comprising extruding through a jetinto' a setting medium a solution of the polypep id in t ieh ora e e acd and en t e n theresultant thread for a period of time not ex ceedingabout 3 minutes in a bath comprising at least one a d h s n ro e gro p nstin of al phatic nion ar e d cont nin from one to six carbon a ms pemolecu e an such acid en ainin on the a carb n stem radical chosen fromthe group consisting of bromide, phenyl and mercaptan groups, so that atleast part of the fibres is converted into the e configuration.

4. A process for the production of fibres from fibre-formingpolypeptides obtained by poly merising alphaanhydrocarboxyamino-carboxylic acids comprising extruding through a jetinto a setting medium a solution of the polypeptidein a solvent given ana configuration and then treating the resultant thread for a period oftime not exceeding about 3 minutes in a bath comprising formic acid sothat at least part of the fibres is converted into the B configuration.

5. A process for the production of fibres from fibre-formingpolypeptides obtained by polymerising alpha anhydrocarboxyamino-carboX-ylic acids comprising extruding through a jet into a setting medium asolution of the polypeptide in dichloracetic acid and then treating theresultant thread for a period of time not exceeding about 3 minutes in abath comprising formic acid so that at least part of the fibres isconverted into the ,8 configuration.

6. A process for the production of fibres from fibre-formingpolypeptides obtained by polymerising alphaanhydrocarboxyamino-carboxylic acids comprising extruding through a jetinto a setting medium a solution of the polypeptide in trichloraceticacid and then treating the resultant thread for a period of time notexceeding about 3 minutes in a bath comprising formic acid so that atleast part of the fibres is converted into the ;& configuration.

7. A process for the production of fibres from fibre-formingpolypeptides obtained by polymerising alphaanhydrocarboxyamino-carboxylic acids comprising extruding through a jetinto a setting medium a solution of the polypeptide in a solvent givingan alpha configuration, stretching the resultant thread and thentreating the resultant thread for a period of time not exceeding about 3minutes in a bath comprising at least one acid chosen from the groupconsisting of aliphatic mono-carbo-xylic acids containing from one tosix carbon atoms per molecule and such acids containing on the alphacarbon atom a radical chosen from the group consisting of bromide,phenyl and mercaptan groups, so that at least part of the fibres isconverted into the beta configuration.

CLEMENT- HENRY BAMFORD. WILLIAM EDWARD HANBY. FRANK HAPPEY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,318,704 Moncrieff et a1 May 11,1943 2,516,162 Tullock July 25, 1950

